The present invention relates to an evaporator, an ice making machine incorporating the evaporator, and a process for making the evaporator.
Automatic ice making machines are well known and are typically found in food and drink service establishments, hotels, motels, sports arenas, and various other places where large quantities of ice are needed on a continuous basis. Some automatic ice making machines produce flaked ice while others produce ice shaped in a variety of configurations, which are commonly referred to as cubes or nuggets.
Automatic ice making machines generally include a refrigeration system having a compressor, a condenser, an evaporator, and an expansion valve. A series of individual ice forming sites are formed on the evaporator and water is supplied to those sites by a water supply system by, for example, trickling or spraying water onto the ice forming site. The run-off of the water is usually recirculated within the water supply. The trickling or spraying methods of supplying water are normally preferred because the methods produce clear ice while the static filled pockets method generally produces white or opaque ice.
Automatic ice making machines are normally controlled as a function of the amount of ice in an ice bin of the ice making machine. When the supply of ice in the ice bin is insufficient, automatic controls cycle the ice making machine through ice production and ice harvest to supplement the supply of ice in the storage portion. In the ice production mode, the refrigeration system operates in a normal manner such that expanding refrigerant in the evaporator removes heat from the series of ice forming sites, freezing the water to form an outwardly growing layer of ice. When the ice thickness reaches a predetermined condition or a specified time period has elapsed, the ice making machine switches to harvest mode.
Typically the harvest mode involves a valve change which directs hot refrigerant gasses to the evaporator. The ice forming locations are heated by the hot refrigerant gasses until the ice in contact with the evaporator begins to thaw. Once the ice falls from the evaporator, it is collected by an appropriate ice bin. When more ice is required, the refrigerant system is switched back to the production mode and the cycle begins again. These cycles continue until there is sufficient ice in the ice bin.